Americans are increasingly reaching for probiotic supplements, but their plates look pretty much the same as they did 15 years ago. A new study published in Clinical Gastroenterology and Hepatology analyzed data from over 54,000 participants across seven cycles of the National Health and Nutrition Examination Survey (2009–2023) and found a dramatic rise in probiotic supplement use — with no corresponding shift in diet.

Probiotic users did consume slightly more fiber than non-users (1.35 g/1,000 kcal more on average), suggesting some overlap between health-conscious behaviors. But for all groups, fiber intake remained well below the recommended 14 g/1,000 kcal — and that gap didn't budge over time.

By the Numbers:

• 786% increase in probiotic use among people under 20 (from 0.63% to 5.58%)
• 287% increase among adults 20+ (from 1.8% to 6.96%)
• Only 26.29% of participants consumed high-microbial content foods the prior day
• 31.17% consumed only low-microbial foods
• Fiber intake remained below the recommended 14 g/1,000 kcal for all groups

Why it matters: The probiotic supplement market is booming, but this study raises an important question: are people using supplements as a shortcut instead of improving their diet? For clinicians, it's a reminder to counsel patients that supplements alone may not replicate the gut health benefits of a fiber-rich, microbiome-supportive diet.